Last updated: ACS (Acute Coronary Syndrome)
on September 06, 2010

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Overview

References:

Review

Bells Palsy

Key facts:

Authors: Rebecca Gray and Steven Barden
Top Tip: Start prednisolone within 72 hours

Key Differential Diagnoses	CVA SOL
Key Investigations	FBC, ESR, CRP U+E, LFT, Bone, Glucose ECG, CXR CT/MRI brain may be indicated to exclude other causes
Key Treatment	PO PREDNISOLONE 60mg od
Key Management Decision	Refer to neurology (usually not necessary)

Background

Introduction	• Bells Palsy describes the sudden paralysis of the facial (VIIth) nerve which renders the patient unable to control the facial muscles on the affected side • Sir Charles Bell first described the anatomy and function of the facial nerve in the 1800s • Many patients make a full recovery but some are left with residual weakness and facial pain • The aetiology is unclear although for some cases the presumed pathophysiology of Bells Palsy is due to inflammation from a viral infection. This theory comes from the fact that during decompressive surgery the facial nerve has been observed to be swollen. These findings have also been seen on MRI scans • The degree of swelling and the part of the facial nerve affected is variable and this gives rise to a spectrum of symptoms • Good review articles: [Ref] ; [Ref] ; [Ref]
Definition	Sudden unilateral facial paralysis of unknown aetiology (lower motor neurone palsy)
Epidemiology	11-40 cases per 100 000 pa Affects men and women equally
Pathology	Thought to be due to ischaemia of nerve, cause unclear ?Viral
Risk factors	• Pregnancy increases the risk threefold – mainly seen in third trimester to first week post partum • Diabetes • Viruses: Herpes Simplex Virus and Herpes Zoster Virus
Erythema Migrans; suggestive of Lyme Disease. Lyme Disease is part of the differential diagnosis of Bells Palsy (see below)
Symptoms	• Sudden onset (over hours) unilateral lower motor neurone facial paralysis – be concerned if onset greater than three weeks (see list of differential diagnoses) • Possible loss of taste over anterior 2/3 of tongue, and inability to make tears • Possible prodrome of ear pain and hyperacusis
Key questions	“Are the symptoms atypical in onset or nature”? “Do I need to do some imaging before starting steroids”?
Signs	• Eye brow droops on affected side • Unable to raise affected eyebrow and wrinkle brow (NB: lower motor neurone palsy) • Difficulty closing eye • If the patient is asked to close their eye and show their teeth the eye ball rotates upwards and outwards: Bell’s Phenomenon • Decreased tear production • Mouth sags on affected side • Unable to blow out cheeks • Unable to whistle • Hyperacusis if the lesion of the facial nerve extends above the point where the branch of the stapedius muscle is given off

Investigation

Blood	FBC, ESR, CRP U+E, LFT, Bone, Glucose ECG, CXR
Key Investigations	CT/MRI brain (normal). If atypical onset or symptoms greater than 3 weeks, do CT or MRI, looking for other causes
Specialist Investigation	CT/MRI brain
Differential Diagnosis	Of LMN VIIth nerve palsy Infective Herpes virus (type 1) Herpes zoster (Ramsay-Hunt syndrome) Lyme disease (or lyme borreliosis) is an emerging infectious disease caused by at least three species of bacteria belonging to the genus Borrelia Otitis media or cholesteatoma Trauma - eg fractures of skull base, haematoma after acupuncture3 Multiple sclerosis Neurological Guillain Barré Mononeurop athy - eg due to diabetes mellitus, sarcoidosis, or amyloidosis Neoplastic Posterior fossa tumours, primary and secondary Parotid gland tumours Other Sjogren's syndrome Hypertension and eclampsia Of UMN VIIth nerve palsy CVA SOL, esp intracranial tumours, primary and secondary Syphilis MS Vasculitides Note: Horners and third nerve palsy cause a ptosis

Treatment

Treatment	• PO PREDNISOLONE 60mg od for 10 day then tapering course – aim to start within 72 hours. Though the evidence for prednisolone in Bells Palsy is not great: [Ref] • Eye protection if unable to fully close eye Note: no evidence for anti-viral treatments: [Ref] ; see references below
Other	• Reassurance - the majority of cases resolve spontaneously - see prognosis. • Eye care - ophthalmologists play an important role in preventing irreversible blindness from corneal exposure. This may be successfully achieved by using lubricating drops hourly and eye ointment at night ± eye patch • Botulinum toxin or surgery (upper lid weighting or tarsorraphy) may also be required temporarily • After the cornea has been protected, but recovery is thought to be unlikely, longer term management of eyelid and facial reanimation may be arranged
Prescribing issues	Ensure prednisolone not continued at high dosage
Key management decision	Refer to neurology or not (usually not necessary)
Admit?	No
Bed plan	None
Referrals	Usually not necessary. If atypical, refer to neurology If patient cannot blink, refer to opthalmology

The Rest

Maxim	"Protecting the eye will protect you"
Complications	• Partial recovery • Irreversible blindness from corneal exposure
Follow-up	GP
Risk stratification	Atypical history should lead to different care pathway
Prognosis	• 75% recover normal function (higher in partial palsy) • One sixth left with some residual weakness • Expect recovery by three weeks or at 4-6 months (speed of nerve regeneration). Any residual deficit after this is likely to be permanent
Don't forget	• Reassurance • Eye protection
Red flags	Atypical history

References

review

Recent developments in Bells Palsy. Holland NJ. BMJ; 329 553-7, 204

A randomised controlled trial of the use of aciclovir and/or prednisolone for the early treatment of Bell’s palsy: the BELLS study. Sullivan FM et al. Health Technology Assessment; 13: No. 47, 2009